Lesley T. Bourne

Where does the black population of South Africa stand on the nutrition transition

OBJECTIVE To review data on selected risk factors related to the emergence of noncommunicable diseases (NCDs) in the black population of South Africa. METHODS Data from existing literature on South African blacks were reviewed with an emphasis placed on changes in diet and the emergence of obesity and related NCDs. DESIGN Review and analysis of secondary data over time relating to diet, physical activity and obesity and relevant to nutrition-related NCDs. SETTINGS Urban, peri-urban and rural areas of South Africa. National prevalence data are also included. SUBJECTS Black adults over the age of 15 years were examined. RESULTS Shifts in dietary intake, to a less prudent pattern, are occurring with apparent increasing momentum, particularly among blacks, who constitute three-quarters of the population. Data have shown that among urban blacks, fat intakes have increased from 16.4% to 26.2% of total energy (a relative increase of 59.7%), while carbohydrate intakes have decreased from 69.3% to 61.7% of total energy (a relative decrease of 10.9%) in the past 50 years. Shifts towards the Western diet are apparent among rural African dwellers as well. The South African Demographic and Health Survey conducted in 1998 revealed that 31.8% of African women (over the age of 15 years) were obese (body mass index (BMI) > or = 30kg m(-2)) and that a further 26.7% were overweight (BMI > or = 25 to <30 kg m(-2)). The obesity prevalence among men of the same age was 6.0%, with 19.4% being overweight. The national prevalence of hypertension in blacks was 24.4%, using the cut-off point of 140/90 mmHg. There are limited data on the populations physical activity patterns. However, the effects of the HIV/AIDS epidemic will become increasingly important. CONCLUSIONS The increasing emergence of NCDs in black South Africans, compounded by the HIV/AIDS pandemic, presents a complex picture for health workers and policy makers. Increasing emphasis needs to be placed on healthy lifestyles.

Urbanization and the Risk for Chronic Diseases of Lifestyle in the Black Population of the Cape Peninsula, South Africa:

Background Men and women have experienced differing patterns of urbanization. Men spent more time in the city as migrant labourers, which could be attributed to the influx control legislation during the apartheid years. Objective To investigate urban exposure among black people of the Cape Peninsula, South Africa, in relation to unhealthy lifestyles and the risk factors for chronic diseases of lifestyle. Methods Blood pressure, height, weight and serum cholesterol were measured in a random sample of 986 persons, aged 15-64 years. Sociodemographic details, urban exposure, dietary intake patterns and personal habits were elicited by questionnaire. An urbanization index (percentage of life spent in a city), the dietary Keys score and body mass index were calculated. Linear regression modelling for cholesterol and hypertension, and multiple correspondence analysis for risk factors and demographic characteristics were performed. Results The degree of urbanization had no effect on total serum cholesterol concentrations, which were very low compared with other groups in South Africa. Hypertension was independently related to age, obesity and the degree of urbanization. Smoking patterns were influenced by the degree of urbanization in women only. Correspondence analysis identified groups with clusters of risk factors: Formal housing-westernized diet-highly urbanized; male-normal weight-increased exercise-alcohol-smoking; female-obesity-non-smoking; and hypertension-ageing. Conclusions Those who had spent larger proportions of their lives in an urban setting tended to have unhealthier lifestyles and higher risk for chronic diseases of lifestyle compared with their less urbanized counterparts. Groups to whom intervention should be targeted were also identified.

Dietary intake and barriers to dietary compliance in black type 2 diabetic patients attending primary health-care services.

OBJECTIVE To determine the dietary intake, practices, knowledge and barriers to dietary compliance of black South African type 2 diabetic patients attending primary health-care services in urban and rural areas. DESIGN A cross-sectional survey. Dietary intake was assessed by three 24-hour recalls, and knowledge and practices by means of a structured questionnaire (n = 133 men, 155 women). In-depth interviews were then conducted with 25 of the patients to explore their underlying beliefs and feelings with respect to their disease. Trained interviewers measured weight, height and blood pressure. A fasting venous blood sample was collected from each participant in order to evaluate glycaemic control. SETTING An urban area (Sheshego) and rural areas near Pietersburg in the Northern Province of South Africa. SUBJECTS The sample comprised 59 men and 75 women from urban areas and 74 men and 80 women from rural areas. All were over 40 years of age, diagnosed with type 2 diabetes for at least one year, and attended primary health-care services in the study area over a 3-month period in 1998. RESULTS Reported dietary results indicate that mean energy intakes were low (< 70% of Recommended Dietary Allowance), 8086-8450 kJ day(-1) and 6967-7382 kJ day(-1) in men and women, respectively. Urban subjects had higher (P < 0.05) intakes of animal protein and lower ratios of polyunsaturated fat to saturated fat than rural subjects. The energy distribution of macronutrients was in line with the recommendations for a prudent diet, with fat intake less than 30%, saturated fat less than 10% and carbohydrate intake greater than 55% of total energy intake. In most respects, nutrient intakes resembled a traditional African diet, although fibre intake was low in terms of the recommended 3-6 g/1000 kJ. More than 90% of patients ate three meals a day, yet only 32-47% had a morning snack and 19-27% had a late evening snack. The majority of patients indicated that they followed a special diet, which had been given to them by a doctor or a nurse. Only 3.4-6.1% were treated by diet alone. Poor glycaemic control was found in both urban and rural participants, with more than half of subjects having fasting plasma glucose above 8 mmol l(-1) and more than 35% having plasma glycosylated haemoglobin level above 8.6%. High triglyceride levels were found in 24 to 25% of men and in 17 to 18% of women. Obesity (body mass index > or = 30 kg m(-2)) was prevalent in 15 to 16% of men compared with 35 to 47% of women; elevated blood pressure (> or = 160/95 mmHg) was least prevalent in rural women (25.9%) and most prevalent in urban men (42.4%). CONCLUSIONS The majority of black, type 2 diabetic patients studied showed poor glycaemic control. Additionally, many had dyslipidaemia, were obese and/or had an elevated blood pressure. Quantitative and qualitative findings indicated that these patients frequently received incorrect and inappropriate dietary advice from health educators.

National fortification of staple foods can make a significant contribution to micronutrient intake of South African adults

BACKGROUND A national survey found that micronutrient deficiencies are prevalent in South African children, particularly calcium, iron, zinc, riboflavin, niacin, vitamin B6, folate, vitamin A, E and C. Mandatory fortification of maize meal and wheat flour were introduced in 2003 to combat some of the deficiencies found in children. To date however, there has not been a national survey on dietary intake in adults. OBJECTIVES The main objectives of this study were to evaluate the micronutrient intake of the diet consumed by the average adult South African by means of secondary data analyses and secondly to evaluate the effects of fortification on selected nutrient intakes. STUDY DESIGN Secondary data analysis was carried out with numerous dietary surveys on adults to create a database that included sampling (and weighting) according to ethnic/urban-rural residence in line with the population census, of which 79% were black Africans and the majority resided in rural areas. The effect of fortification was evaluated by substituting fortified foods in the diet for the unfortified products. SUBJECTS The combined database used in this study comprised 3229 adults. RESULTS Mean calcium, iron, folate and vitamin B6 intakes were very low particularly in women. Mean intakes of most micronutrients were lower in rural areas. Fortification of maize meal and wheat flour (bread) raised mean levels of thiamine, riboflavin, niacin, vitamin B6 and folate above the recommended nutrient intakes (RNIs). In women, despite fortification, mean iron intakes remained below the RNIs, as did calcium since it was not in the fortification mix. CONCLUSION The average dietary intake of adults was of poor nutrient density, particularly in rural areas. Fortification of maize meal and wheat flour (bread) considerably improved mean vitamin B6, thiamine, riboflavin, niacin, folate and iron intakes as well as the overall mean adequacy ratio of the diet.

Level of physical activity and CHD risk factors in black South African men

Coronary heart disease (CHD) is uncommonly low among black South Africans. Although dietary and genetic influences probably contribute to their favorable serum lipid profile, other cardioprotective factors may also play a significant role in explaining the low incidence of CHD. From a socioeconomic perspective, it appears that the black community engages in regular physical activity (PA) more so than other populations. Since data are lacking, our aim was to provide preliminary data on the association between PA and the traditional CHD risk factors. The sample consisted of 212 working, middle-aged men drawn from an epidemiological database on the African population of metropolitan Cape Town. Analysis of responses to basic questions on PA behavior indicated i) 43% of the sample were employed in jobs requiring moderate to strenuous PA, and ii) the most favorable blood pressure and serum lipid profiles were associated with low to moderate levels of habitual exercise. As this community becomes more urbanized, job-related PA as well as PA of daily living will decline. The need for sports and leisure-time PA programs will become more important and should be considered as part of a public health strategic plan.

An assessment of preliminary food-based dietary guidelines for infants 6–12 months of age in the Little Karoo area of the Western Cape Province of South Africa

OBJECTIVE This study aimed to assess mothers/caregivers understanding, practical application and cultural acceptability of a preliminary set of South African food-based dietary guidelines (FBDGs) for children aged 6-12 months living in the Little Karoo area of the Western Cape Province. DESIGN An observational, descriptive and cross-sectional study design was followed. Focus group interviews, recorded on videotape, were analysed for qualitative data. Quantitative questionnaires measured knowledge and comprehension of guidelines, perceived constraints to compliance with and importance of guidelines as well as socio demographic data prior to the focus group interviews. SETTING Afrikaans-, English- and Xhosa-speaking communities of the Little Karoo area of the Western Cape Province of South Africa, including the urban areas of Oudtshoorn, Bongulethu, Bridgton, Toekomsrus and the adjacent rural areas of Dysselsdorp, Calitzdorp, Uniondale, Ladismith and Zoar. SUBJECTS Sixty-four mothers or caregivers to infants 6-12 months of age were included in the sample. RESULTS Information obtained through the questionnaires supported what was said during discussions. Although perceived as important by the majority of respondents, some of the guidelines were not well understood without prior explanation. Such guidelines were those pertaining to meal frequency and cup feeding, while application of the guideline to prolonged breast-feeding seemed the most problematic. CONCLUSIONS The FBDGs for this age group will have to be supported by extensive and appropriate educational material to be effective when introduced to the public. The fact that the applicability of the guideline to prolonged breast-feeding seemed to be the most problematic is a cause for concern.